1. Field of the Invention
The present invention relates to navigational devices for use by the visually impaired and specifically to improved white cane devices having a white or pink noise generator incorporated into the tip thereof.
2. Background and Related Art
A white cane is used by many people who are blind or visually impaired. Its primary uses are typically as a mobility tool and as a courtesy to others. White canes obtained their name from the white coloring that was historically adopted for mobility canes to improve the ability of others to see that a mobility cane is in use. There are various varieties of white canes serving slightly different needs. A traditional white cane, also known as a long cane or “Hoover” cane after Dr. Richard Hoover, is designed primarily as a mobility tool used to detect objects in the path of a user. Cane length of a traditional white cane depends on the height of the user, and traditionally extends from the floor to the user's sternum, although some favor the use of even longer canes.
A guide cane is a shorter cane that generally extends from the floor to the user's waist, thus having a more limited mobility function. A guide cane is most useful for scanning for curbs and steps, but can also be used diagonally across the body for protection, warning the user of obstacles immediately ahead. An identification cane (ID cane) is used primarily to alert others as to the bearer's visual impairment. The ID cane is often a lighter and shorter cane and may have no use as a mobility tool.
A support cane may be designed primarily to offer physical stability to a visually impaired user. The support cane may also work as a means of identification by virtue of its color. The support cane has limited potential as a mobility device other than through the physical support offered to the user. A kiddie cane works the same as an adult long cane, but is sized and designed for use by children.
The various white canes are often made from aluminum, graphite-reinforced plastic, other fiber-reinforced plastics, and the like. White canes can come with a variety of tips depending upon user preference. Additionally, white canes can be either collapsible or straight: the lightness and greater strength of the straight canes allows greater mobility and safety, though collapsible canes can be stored with more ease for some advantages in crowded areas.
Dr. Richard Hoover first developed what is now the standard method of long cane training. The basic technique is to swing the cane from the center of the body back and forth before the feet—the cane should be swept before the rear foot as the person steps. While this method is helpful in identifying obstacles and dangers to the visually-impaired user, the method has certain limitations.
For example, use of the Hoover method with existing white canes is limited to detection of objects that come in physical contact with the sweeping white cane. If the white cane passes underneath an obstacle that is located in the path of the user but does not extend to the ground, the visually impaired user may not become aware of the obstacle before a portion of his or her body strikes the obstacle. The use of existing standard white canes is also limited in that the range of detection of obstacles is limited to the length of the white cane.
Attempts have been made to try to address the limitations of traditional white canes. One mechanism that has been attempted to address these limitations is to incorporate sensors into white canes that allow for longer-range detection of obstacles with some sort of feedback to the visually-impaired user. For example, ultrasonic and/or radar generators paired with appropriate detectors have been incorporated into certain white canes to permit the white cane itself to detect upcoming obstacles not within the range of physical contact with the white cane. The white cane then can provide some sort of feedback to the visually impaired user, such as auditory feedback (beeps, spoken warnings, and the like) and tactile feedback (such as through haptic technology incorporated into a handle of the white cane).
Despite the advances promised by such attempts at improvements to traditional white canes, significant problems still remain. Generally, the attempted improvements greatly increase the complexity of the white cane and its manufacture, with accompanying increases in cost as well as weight. The current systems are also fairly complex, as the systems generally require the white cane itself to identify an obstacle, determine the location/distance of the identified obstacle, and determine when and how to notify the visually impaired user. Haptic notification systems are often non-intuitive and require significant training for the visually impaired user to learn how to interpret the white cane's notification of an impending obstacle. Audible notification systems may become annoying both to the visually impaired user as well as to others in the general vicinity of the white cane, especially in quiet environments.
The at times greatly increased weight of the modified white canes increases the difficulty of use of the white cane. In the short term, the user may have to use increased force to utilize the Hoover method for sweeping the white cane from side to side. In the long term, the user may suffer from increased fatigue. The complexity of the modified white canes may lead to other problems, including a possibility of failure of the detection devices at any number of points, which may result in complete failure of the incorporated detection and notification system.
In many cases, the attempts at improving the traditional white canes still fail to address many of the problems encountered by users of traditional white canes. The white canes incorporating active detection features may fail to identify certain types of obstacles or hazards, including obstacles or hazards in the visually impaired user's path that fail to extend downward sufficiently for proper detection.
In short, existing attempts to improve traditional white cane have failed to address the needs of the visually impaired community.